A common practice in collecting fibrous material is to direct the fibrous material as a stream or veil toward a collection surface, such as a foraminous conveyor, which receives the fibers and forms a mat or fibrous web thereon. For various reasons it is desirable to produce wider and wider mats or packs on the collection surface, particularly wider than the width of the stream of fibers. It is therefore desirable to distribute the fibers in order to cover the entire width of the collection surface. It is often the case that the collection conveyor has a width of up to six times or more of the width of the stream of fibrous material.
In order to evenly distribute the fibers from the stream across the entire width of the collection surface it is a common practice to lap the stream of fibers with an oscillating cylinder resembling an open-bottomed bucket. The oscillating bucket distributes the fibrous material rapidly from side to side of the collection surface, thereby providing relatively even distribution. Another method commonly utilized in distributing streams of fibrous material is directing the stream toward the center of the collection conveyor, and diverting some or all of the stream periodically to either one side or the other side of the conveyor with blasts of air. The air blasts are directed generally perpendicularly to the stream of fibrous material to impart a sideways distributive force thereto.
One of the problems with the above method for distributing streams of fibers is that they all consume significant amounts of energy. Also, the process of lapping the entire stream of fibers can cause nonuniformity as the fibers are laid down on the collection surface. The use of air blasts to distribute the stream of fibers causes problems because the fibers are accelerated toward the collection surface and have a tendency to bounce or blow back from the collection surface, thereby necessitating suction fans beneath the collection surface to hold the pack down onto the collection surface. The energy required to operate such suction fans is substantial, and all of the exhausted air must be treated for pollution control purposes. Excessive suction by the fans tends to crush some of the fibrous material in the pack. Also, the air blasts increase the general level of turbulence in the pack forming hood. The oscillating buckets lapper is limited to the production of relatively narrow fibrous packs, and is not suitable for use on wide machines. The method and apparatus of the invention are directed towards the solution of the above problems.